DENVER, CO - SEPTEMBER 27: A perigee full moon, or supermoon, is seen during a total lunar eclipse behind The Colorado State Capitol building on September 27, 2015, in Denver, Colorado. The combination of a supermoon and total lunar eclipse last occurred in 1982 and will not happen again until 2033. (Photo by (NASA/Bill Ingalls)

Democratic Sen. Mike Foote's bill
would have Colorado join 11 states and the District of Columbia in what's called the National Popular Vote Interstate Compact.

It would replace the Electoral College, in which 270 electoral votes are needed to win the U.S. presidency. Compact proponents say
it would go into effect once enough states with 270 votes enter the pact.

Colorado has nine electoral votes. Compact members currently have 172 electors.

The bill, which passed on party lines Tuesday, goes to the Democrat-controlled House.

Several presidents, most recently Donald Trump in 2016, were elected with an electoral college majority despite losing the popular vote.

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